Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • School
  • Provide Solution For R.D. Sharma Maths Class 12 Chapter 30 Probaility Exercise 30.5 Question 18 Maths Textbook Solution.

Provide Solution For  R.D. Sharma Maths Class 12 Chapter 30 Probaility  Exercise 30.5 Question 18 Maths Textbook Solution.

Answers (1)

Answer:\frac{67}{256}

Hint: You must know the rules of finding probability functions.

Given: Bag contains = (4W+5R+7B) balls

Solution

No. of white balls = 4

No. of black balls = 7

No. of red balls = 5

 

Total balls = 16

 

No. of ways in which 4 balls can be drawn from 16 balls=16C_{4}

Let A = getting at least two white balls = getting 2, 3, 4 white balls

No. of ways of choosing 2 white balls =4C_{2}\times 12C_{2}

No. of ways of choosing 3 white balls =4C_{3}\times 12C_{1}

No. of ways of choosing 4 white balls =4C_{4}\times 12C_{0}

\begin{aligned} &P(A)=\frac{4 C_{2} \times 12 C_{2}+4 C_{3} \times 12 C_{1}+4 C_{4} \times 12 C_{0}}{16 C_{4}} \\ &=\frac{4 !}{2 ! 2 !} \times \frac{12 !}{2 ! 10 !}+\frac{4 !}{3 !} \times \frac{12 !}{11 !}+\frac{4 !}{4 ! 0 !} \times \frac{12 !}{12 !} \\ &=\frac{16 !}{4 ! 2 !} \\ &=\frac{67}{256} \end{aligned}

Posted by

infoexpert21

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads

Similar Questions

Trending Articles/News

anam-khan

CBSE Board exams twice a year from 2025, no plan for semesters: MoE
anam-khan

CBSE Class 12 board exams 2025 to have 50% competency-based questions; no change in 10th
anam-khan

CBSE Class 12 board exams 2024 over; expected result date, trends of last 10 years

Latest Question